It depends on the game whether it requires more cores/threads or not. Battlefield 1 benefits from extra cores/threads, player unknown's battleground doesn't. Tweaktown found that the i5 7600k (stock) outperformed the ryzen 1600x by around 32%.
http://www.tweaktown.com/articles/8189/playerunknowns-battlegrounds-benchmarked-cpu-gpu-war/index7.html
In pure gaming intel usually has a slight edge, even the i5 vs the 1600x. It's not a huge gap like it used to be, but there's a noticeable lead.
http://www.pcgamer.com/new-games-2017/
It could very well be that future games will become more heavily threaded and need more cores but it's speculation. The same predictions were made last year, the year before that, the year before that. Many were suggesting that the fx lineup due to having more cores would end up seeing a boost in gaming back in 2014, 2015. Here we are in 2017 and only a small minority of games are making use of hyper threading, much less requiring 6-8 cores. Meanwhile ryzen's been released, fx has all but been forgotten and the predictions from years past have yet to really materialize.
Much like the hype over dx12, we're several years beyond the release of win10 which brought dx12 support with it. Games are slowly trying to implement it or go back and add portions of dx12 to existing games and many of the benchmarks show actual dx12 performance to be worse than dx11. Basing performance off what 'could be' vs 'what is' can be risky, no telling if it will or when it will actually pay off.
On the bright side, both intel and ryzen are quite capable, ryzen isn't gimped like fx was so it's more of a choice between great and really great (depending on the scenario). You won't be stuck picking one and have it turn out to be horrible.